Answer: 37
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Explanation:
a = 1 is the first term
d = 2 is the common difference, since we add 2 to each term to get the next term.
The nth term is a+d(n-1) which becomes 1+2(n-1). That simplifies to 2n-1
The last step is to plug in n = 19 and you should get 2(19)-1 = 37
